HEAT oven to 350°F.
LINE 13x9-inch pan with foil, with ends of foil extending over sides. Grease foil. Mix crumbs, 1/2 cup nuts and butter; press onto bottom of pan.
BEAT cream cheese and sugar in large bowl with mixer until blended. Add sour cream and vanilla; mix well. Add eggs, 1 at a time, mixing on low speed after each just until blended. Pour over crust.
BAKE 45 min. or until centre is almost set. Cool completely. Refrigerate 4 hours. Drizzle with caramel topping; sprinkle with remaining nuts. Use foil handles to lift dessert from pan before cutting into bars.